Injection blow-molding systems are well known in the art. A variety of different sophisticated injection blow-molding machines have been developed through the years.
Most known injection blow-molding machines use a vertical clamp and rotating tables, and require a complete mold change to produce bottles of different shapes and configurations. This leads to very expensive tooling, long lead times and high cost in new product development, time consuming and complicated tooling setup, and high cost in repairs of damaged tools, since the entire mold must be taken out of the machine to repair one damaged component.
A machine with a horizontal clamp and shuttle plate moving perpendicular to the machine axis is described in U.S. Pat. No. 4,065,246 to Marcus. However, this patent does not provide a specific description of how different parts of this machine are formed and operate. Further, this patent does not provide means for replacing tooling components in the machine, and moreover, does not provide means for stack height reduction to accommodate a standard injection molding machine with limited daylight in the manufacturing of injection blow molding products. In other words, with this machine, the entire stack height, which is in the horizontal direction, is not reduced. The stack height is the distance between the movable platen and the immovable platen with the machine closed and the mold in the machine, that is, the thickness of the mold itself. "Daylight" is the distance between the movable platen and the immovable platen with the machine open. The opening distance permits for interchangeable tooling.
There are machines with modular tooling set-up known to the industry, and developed by the inventor of the present invention, but not described in any publications. However, these machines have a mold in them with an overall stack height of around 32-35 inches, and to provide an opening of about 16-20 inches, would require daylight of about 48-54 inches. This stack height, however, does not permit the use of a small standard injection-molding machine as a base machine. Using special injection machines with extended daylight and large tonnage which is not needed in manufacturing of injection molded parisons is not economical. At the same time, when using a big machine, a large number of cavities must be formed to make the machine profitable. A large number of cavities, on the other hand, defeats the purpose of interchangeability of the machine components, because every time a component has to be changed, the machine must be stopped and restarted again. It is a complicated process to restart a machine with a large number of cavities varying to a great deal in shapes and sizes, and this leads to a lot of wasted material during the start-up and a great loss in production. Small machines will provide better start-ups, will be more flexible in production scheduling, and enable the manufacturers to run products made from different materials and colors more readily.
The present invention, on the other hand, enables manufacturers of plastic containers to move the machine close to the customer and provide the customer with all different sizes and shapes needed, without the additional expense of shipping and packing of the finished product, while also reducing the stack height of the machine.